1 //===- DebugInfoMetadata.cpp - Implement debug info metadata --------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the debug info Metadata classes.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/IR/DebugInfoMetadata.h"
15 #include "LLVMContextImpl.h"
16 #include "MetadataImpl.h"
17 #include "llvm/ADT/StringSwitch.h"
18 #include "llvm/IR/Function.h"
19 
20 using namespace llvm;
21 
22 DILocation::DILocation(LLVMContext &C, StorageType Storage, unsigned Line,
23                        unsigned Column, ArrayRef<Metadata *> MDs)
24     : MDNode(C, DILocationKind, Storage, MDs) {
25   assert((MDs.size() == 1 || MDs.size() == 2) &&
26          "Expected a scope and optional inlined-at");
27 
28   // Set line and column.
29   assert(Column < (1u << 16) && "Expected 16-bit column");
30 
31   SubclassData32 = Line;
32   SubclassData16 = Column;
33 }
34 
35 static void adjustColumn(unsigned &Column) {
36   // Set to unknown on overflow.  We only have 16 bits to play with here.
37   if (Column >= (1u << 16))
38     Column = 0;
39 }
40 
41 DILocation *DILocation::getImpl(LLVMContext &Context, unsigned Line,
42                                 unsigned Column, Metadata *Scope,
43                                 Metadata *InlinedAt, StorageType Storage,
44                                 bool ShouldCreate) {
45   // Fixup column.
46   adjustColumn(Column);
47 
48   if (Storage == Uniqued) {
49     if (auto *N =
50             getUniqued(Context.pImpl->DILocations,
51                        DILocationInfo::KeyTy(Line, Column, Scope, InlinedAt)))
52       return N;
53     if (!ShouldCreate)
54       return nullptr;
55   } else {
56     assert(ShouldCreate && "Expected non-uniqued nodes to always be created");
57   }
58 
59   SmallVector<Metadata *, 2> Ops;
60   Ops.push_back(Scope);
61   if (InlinedAt)
62     Ops.push_back(InlinedAt);
63   return storeImpl(new (Ops.size())
64                        DILocation(Context, Storage, Line, Column, Ops),
65                    Storage, Context.pImpl->DILocations);
66 }
67 
68 unsigned DINode::getFlag(StringRef Flag) {
69   return StringSwitch<unsigned>(Flag)
70 #define HANDLE_DI_FLAG(ID, NAME) .Case("DIFlag" #NAME, Flag##NAME)
71 #include "llvm/IR/DebugInfoFlags.def"
72       .Default(0);
73 }
74 
75 const char *DINode::getFlagString(unsigned Flag) {
76   switch (Flag) {
77   default:
78     return "";
79 #define HANDLE_DI_FLAG(ID, NAME)                                               \
80   case Flag##NAME:                                                             \
81     return "DIFlag" #NAME;
82 #include "llvm/IR/DebugInfoFlags.def"
83   }
84 }
85 
86 unsigned DINode::splitFlags(unsigned Flags,
87                             SmallVectorImpl<unsigned> &SplitFlags) {
88   // Accessibility and member pointer flags need to be specially handled, since
89   // they're packed together.
90   if (unsigned A = Flags & FlagAccessibility) {
91     if (A == FlagPrivate)
92       SplitFlags.push_back(FlagPrivate);
93     else if (A == FlagProtected)
94       SplitFlags.push_back(FlagProtected);
95     else
96       SplitFlags.push_back(FlagPublic);
97     Flags &= ~A;
98   }
99   if (unsigned R = Flags & FlagPtrToMemberRep) {
100     if (R == FlagSingleInheritance)
101       SplitFlags.push_back(FlagSingleInheritance);
102     else if (R == FlagMultipleInheritance)
103       SplitFlags.push_back(FlagMultipleInheritance);
104     else
105       SplitFlags.push_back(FlagVirtualInheritance);
106     Flags &= ~R;
107   }
108 
109 #define HANDLE_DI_FLAG(ID, NAME)                                               \
110   if (unsigned Bit = Flags & ID) {                                             \
111     SplitFlags.push_back(Bit);                                                 \
112     Flags &= ~Bit;                                                             \
113   }
114 #include "llvm/IR/DebugInfoFlags.def"
115 
116   return Flags;
117 }
118 
119 DIScopeRef DIScope::getScope() const {
120   if (auto *T = dyn_cast<DIType>(this))
121     return T->getScope();
122 
123   if (auto *SP = dyn_cast<DISubprogram>(this))
124     return SP->getScope();
125 
126   if (auto *LB = dyn_cast<DILexicalBlockBase>(this))
127     return LB->getScope();
128 
129   if (auto *NS = dyn_cast<DINamespace>(this))
130     return NS->getScope();
131 
132   if (auto *M = dyn_cast<DIModule>(this))
133     return M->getScope();
134 
135   assert((isa<DIFile>(this) || isa<DICompileUnit>(this)) &&
136          "Unhandled type of scope.");
137   return nullptr;
138 }
139 
140 StringRef DIScope::getName() const {
141   if (auto *T = dyn_cast<DIType>(this))
142     return T->getName();
143   if (auto *SP = dyn_cast<DISubprogram>(this))
144     return SP->getName();
145   if (auto *NS = dyn_cast<DINamespace>(this))
146     return NS->getName();
147   if (auto *M = dyn_cast<DIModule>(this))
148     return M->getName();
149   assert((isa<DILexicalBlockBase>(this) || isa<DIFile>(this) ||
150           isa<DICompileUnit>(this)) &&
151          "Unhandled type of scope.");
152   return "";
153 }
154 
155 #ifndef NDEBUG
156 static bool isCanonical(const MDString *S) {
157   return !S || !S->getString().empty();
158 }
159 #endif
160 
161 GenericDINode *GenericDINode::getImpl(LLVMContext &Context, unsigned Tag,
162                                       MDString *Header,
163                                       ArrayRef<Metadata *> DwarfOps,
164                                       StorageType Storage, bool ShouldCreate) {
165   unsigned Hash = 0;
166   if (Storage == Uniqued) {
167     GenericDINodeInfo::KeyTy Key(Tag, Header, DwarfOps);
168     if (auto *N = getUniqued(Context.pImpl->GenericDINodes, Key))
169       return N;
170     if (!ShouldCreate)
171       return nullptr;
172     Hash = Key.getHash();
173   } else {
174     assert(ShouldCreate && "Expected non-uniqued nodes to always be created");
175   }
176 
177   // Use a nullptr for empty headers.
178   assert(isCanonical(Header) && "Expected canonical MDString");
179   Metadata *PreOps[] = {Header};
180   return storeImpl(new (DwarfOps.size() + 1) GenericDINode(
181                        Context, Storage, Hash, Tag, PreOps, DwarfOps),
182                    Storage, Context.pImpl->GenericDINodes);
183 }
184 
185 void GenericDINode::recalculateHash() {
186   setHash(GenericDINodeInfo::KeyTy::calculateHash(this));
187 }
188 
189 #define UNWRAP_ARGS_IMPL(...) __VA_ARGS__
190 #define UNWRAP_ARGS(ARGS) UNWRAP_ARGS_IMPL ARGS
191 #define DEFINE_GETIMPL_LOOKUP(CLASS, ARGS)                                     \
192   do {                                                                         \
193     if (Storage == Uniqued) {                                                  \
194       if (auto *N = getUniqued(Context.pImpl->CLASS##s,                        \
195                                CLASS##Info::KeyTy(UNWRAP_ARGS(ARGS))))         \
196         return N;                                                              \
197       if (!ShouldCreate)                                                       \
198         return nullptr;                                                        \
199     } else {                                                                   \
200       assert(ShouldCreate &&                                                   \
201              "Expected non-uniqued nodes to always be created");               \
202     }                                                                          \
203   } while (false)
204 #define DEFINE_GETIMPL_STORE(CLASS, ARGS, OPS)                                 \
205   return storeImpl(new (array_lengthof(OPS))                                   \
206                        CLASS(Context, Storage, UNWRAP_ARGS(ARGS), OPS),        \
207                    Storage, Context.pImpl->CLASS##s)
208 #define DEFINE_GETIMPL_STORE_NO_OPS(CLASS, ARGS)                               \
209   return storeImpl(new (0u) CLASS(Context, Storage, UNWRAP_ARGS(ARGS)),        \
210                    Storage, Context.pImpl->CLASS##s)
211 #define DEFINE_GETIMPL_STORE_NO_CONSTRUCTOR_ARGS(CLASS, OPS)                   \
212   return storeImpl(new (array_lengthof(OPS)) CLASS(Context, Storage, OPS),     \
213                    Storage, Context.pImpl->CLASS##s)
214 
215 DISubrange *DISubrange::getImpl(LLVMContext &Context, int64_t Count, int64_t Lo,
216                                 StorageType Storage, bool ShouldCreate) {
217   DEFINE_GETIMPL_LOOKUP(DISubrange, (Count, Lo));
218   DEFINE_GETIMPL_STORE_NO_OPS(DISubrange, (Count, Lo));
219 }
220 
221 DIEnumerator *DIEnumerator::getImpl(LLVMContext &Context, int64_t Value,
222                                     MDString *Name, StorageType Storage,
223                                     bool ShouldCreate) {
224   assert(isCanonical(Name) && "Expected canonical MDString");
225   DEFINE_GETIMPL_LOOKUP(DIEnumerator, (Value, Name));
226   Metadata *Ops[] = {Name};
227   DEFINE_GETIMPL_STORE(DIEnumerator, (Value), Ops);
228 }
229 
230 DIBasicType *DIBasicType::getImpl(LLVMContext &Context, unsigned Tag,
231                                   MDString *Name, uint64_t SizeInBits,
232                                   uint64_t AlignInBits, unsigned Encoding,
233                                   StorageType Storage, bool ShouldCreate) {
234   assert(isCanonical(Name) && "Expected canonical MDString");
235   DEFINE_GETIMPL_LOOKUP(DIBasicType,
236                         (Tag, Name, SizeInBits, AlignInBits, Encoding));
237   Metadata *Ops[] = {nullptr, nullptr, Name};
238   DEFINE_GETIMPL_STORE(DIBasicType, (Tag, SizeInBits, AlignInBits, Encoding),
239                        Ops);
240 }
241 
242 DIDerivedType *DIDerivedType::getImpl(
243     LLVMContext &Context, unsigned Tag, MDString *Name, Metadata *File,
244     unsigned Line, Metadata *Scope, Metadata *BaseType, uint64_t SizeInBits,
245     uint64_t AlignInBits, uint64_t OffsetInBits, unsigned Flags,
246     Metadata *ExtraData, StorageType Storage, bool ShouldCreate) {
247   assert(isCanonical(Name) && "Expected canonical MDString");
248   DEFINE_GETIMPL_LOOKUP(DIDerivedType,
249                         (Tag, Name, File, Line, Scope, BaseType, SizeInBits,
250                          AlignInBits, OffsetInBits, Flags, ExtraData));
251   Metadata *Ops[] = {File, Scope, Name, BaseType, ExtraData};
252   DEFINE_GETIMPL_STORE(
253       DIDerivedType, (Tag, Line, SizeInBits, AlignInBits, OffsetInBits, Flags),
254       Ops);
255 }
256 
257 DICompositeType *DICompositeType::getImpl(
258     LLVMContext &Context, unsigned Tag, MDString *Name, Metadata *File,
259     unsigned Line, Metadata *Scope, Metadata *BaseType, uint64_t SizeInBits,
260     uint64_t AlignInBits, uint64_t OffsetInBits, unsigned Flags,
261     Metadata *Elements, unsigned RuntimeLang, Metadata *VTableHolder,
262     Metadata *TemplateParams, MDString *Identifier, StorageType Storage,
263     bool ShouldCreate) {
264   assert(isCanonical(Name) && "Expected canonical MDString");
265 
266   // Keep this in sync with buildODRType.
267   DEFINE_GETIMPL_LOOKUP(
268       DICompositeType, (Tag, Name, File, Line, Scope, BaseType, SizeInBits,
269                         AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
270                         VTableHolder, TemplateParams, Identifier));
271   Metadata *Ops[] = {File,     Scope,        Name,           BaseType,
272                      Elements, VTableHolder, TemplateParams, Identifier};
273   DEFINE_GETIMPL_STORE(DICompositeType, (Tag, Line, RuntimeLang, SizeInBits,
274                                          AlignInBits, OffsetInBits, Flags),
275                        Ops);
276 }
277 
278 DICompositeType *DICompositeType::buildODRType(
279     LLVMContext &Context, MDString &Identifier, unsigned Tag, MDString *Name,
280     Metadata *File, unsigned Line, Metadata *Scope, Metadata *BaseType,
281     uint64_t SizeInBits, uint64_t AlignInBits, uint64_t OffsetInBits,
282     unsigned Flags, Metadata *Elements, unsigned RuntimeLang,
283     Metadata *VTableHolder, Metadata *TemplateParams) {
284   assert(!Identifier.getString().empty() && "Expected valid identifier");
285   if (!Context.isODRUniquingDebugTypes())
286     return nullptr;
287   auto *&CT = (*Context.pImpl->DITypeMap)[&Identifier];
288   if (!CT)
289     return CT = DICompositeType::getDistinct(
290                Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
291                AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
292                VTableHolder, TemplateParams, &Identifier);
293 
294   // Only mutate CT if it's a forward declaration and the new operands aren't.
295   assert(CT->getRawIdentifier() == &Identifier && "Wrong ODR identifier?");
296   if (!CT->isForwardDecl() || (Flags & DINode::FlagFwdDecl))
297     return CT;
298 
299   // Mutate CT in place.  Keep this in sync with getImpl.
300   CT->mutate(Tag, Line, RuntimeLang, SizeInBits, AlignInBits, OffsetInBits,
301              Flags);
302   Metadata *Ops[] = {File,     Scope,        Name,           BaseType,
303                      Elements, VTableHolder, TemplateParams, &Identifier};
304   assert((std::end(Ops) - std::begin(Ops)) == (int)CT->getNumOperands() &&
305          "Mismatched number of operands");
306   for (unsigned I = 0, E = CT->getNumOperands(); I != E; ++I)
307     if (Ops[I] != CT->getOperand(I))
308       CT->setOperand(I, Ops[I]);
309   return CT;
310 }
311 
312 DICompositeType *DICompositeType::getODRType(
313     LLVMContext &Context, MDString &Identifier, unsigned Tag, MDString *Name,
314     Metadata *File, unsigned Line, Metadata *Scope, Metadata *BaseType,
315     uint64_t SizeInBits, uint64_t AlignInBits, uint64_t OffsetInBits,
316     unsigned Flags, Metadata *Elements, unsigned RuntimeLang,
317     Metadata *VTableHolder, Metadata *TemplateParams) {
318   assert(!Identifier.getString().empty() && "Expected valid identifier");
319   if (!Context.isODRUniquingDebugTypes())
320     return nullptr;
321   auto *&CT = (*Context.pImpl->DITypeMap)[&Identifier];
322   if (!CT)
323     CT = DICompositeType::getDistinct(
324         Context, Tag, Name, File, Line, Scope, BaseType, SizeInBits,
325         AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang, VTableHolder,
326         TemplateParams, &Identifier);
327   return CT;
328 }
329 
330 DICompositeType *DICompositeType::getODRTypeIfExists(LLVMContext &Context,
331                                                      MDString &Identifier) {
332   assert(!Identifier.getString().empty() && "Expected valid identifier");
333   if (!Context.isODRUniquingDebugTypes())
334     return nullptr;
335   return Context.pImpl->DITypeMap->lookup(&Identifier);
336 }
337 
338 DISubroutineType *DISubroutineType::getImpl(LLVMContext &Context,
339                                             unsigned Flags, uint8_t CC,
340                                             Metadata *TypeArray,
341                                             StorageType Storage,
342                                             bool ShouldCreate) {
343   DEFINE_GETIMPL_LOOKUP(DISubroutineType, (Flags, CC, TypeArray));
344   Metadata *Ops[] = {nullptr, nullptr, nullptr, TypeArray};
345   DEFINE_GETIMPL_STORE(DISubroutineType, (Flags, CC), Ops);
346 }
347 
348 DIFile *DIFile::getImpl(LLVMContext &Context, MDString *Filename,
349                         MDString *Directory, StorageType Storage,
350                         bool ShouldCreate) {
351   assert(isCanonical(Filename) && "Expected canonical MDString");
352   assert(isCanonical(Directory) && "Expected canonical MDString");
353   DEFINE_GETIMPL_LOOKUP(DIFile, (Filename, Directory));
354   Metadata *Ops[] = {Filename, Directory};
355   DEFINE_GETIMPL_STORE_NO_CONSTRUCTOR_ARGS(DIFile, Ops);
356 }
357 
358 DICompileUnit *DICompileUnit::getImpl(
359     LLVMContext &Context, unsigned SourceLanguage, Metadata *File,
360     MDString *Producer, bool IsOptimized, MDString *Flags,
361     unsigned RuntimeVersion, MDString *SplitDebugFilename,
362     unsigned EmissionKind, Metadata *EnumTypes, Metadata *RetainedTypes,
363     Metadata *GlobalVariables, Metadata *ImportedEntities, Metadata *Macros,
364     uint64_t DWOId, bool SplitDebugInlining, StorageType Storage,
365     bool ShouldCreate) {
366   assert(Storage != Uniqued && "Cannot unique DICompileUnit");
367   assert(isCanonical(Producer) && "Expected canonical MDString");
368   assert(isCanonical(Flags) && "Expected canonical MDString");
369   assert(isCanonical(SplitDebugFilename) && "Expected canonical MDString");
370 
371   Metadata *Ops[] = {
372       File,      Producer,      Flags,           SplitDebugFilename,
373       EnumTypes, RetainedTypes, GlobalVariables, ImportedEntities,
374       Macros};
375   return storeImpl(new (array_lengthof(Ops))
376                        DICompileUnit(Context, Storage, SourceLanguage,
377                                      IsOptimized, RuntimeVersion, EmissionKind,
378                                      DWOId, SplitDebugInlining, Ops),
379                    Storage);
380 }
381 
382 Optional<DICompileUnit::DebugEmissionKind>
383 DICompileUnit::getEmissionKind(StringRef Str) {
384   return StringSwitch<Optional<DebugEmissionKind>>(Str)
385       .Case("NoDebug", NoDebug)
386       .Case("FullDebug", FullDebug)
387       .Case("LineTablesOnly", LineTablesOnly)
388       .Default(None);
389 }
390 
391 const char *DICompileUnit::EmissionKindString(DebugEmissionKind EK) {
392   switch (EK) {
393   case NoDebug:        return "NoDebug";
394   case FullDebug:      return "FullDebug";
395   case LineTablesOnly: return "LineTablesOnly";
396   }
397   return nullptr;
398 }
399 
400 DISubprogram *DILocalScope::getSubprogram() const {
401   if (auto *Block = dyn_cast<DILexicalBlockBase>(this))
402     return Block->getScope()->getSubprogram();
403   return const_cast<DISubprogram *>(cast<DISubprogram>(this));
404 }
405 
406 DILocalScope *DILocalScope::getNonLexicalBlockFileScope() const {
407   if (auto *File = dyn_cast<DILexicalBlockFile>(this))
408     return File->getScope()->getNonLexicalBlockFileScope();
409   return const_cast<DILocalScope *>(this);
410 }
411 
412 DISubprogram *DISubprogram::getImpl(
413     LLVMContext &Context, Metadata *Scope, MDString *Name,
414     MDString *LinkageName, Metadata *File, unsigned Line, Metadata *Type,
415     bool IsLocalToUnit, bool IsDefinition, unsigned ScopeLine,
416     Metadata *ContainingType, unsigned Virtuality, unsigned VirtualIndex,
417     int ThisAdjustment, unsigned Flags, bool IsOptimized, Metadata *Unit,
418     Metadata *TemplateParams, Metadata *Declaration, Metadata *Variables,
419     StorageType Storage, bool ShouldCreate) {
420   assert(isCanonical(Name) && "Expected canonical MDString");
421   assert(isCanonical(LinkageName) && "Expected canonical MDString");
422   DEFINE_GETIMPL_LOOKUP(
423       DISubprogram,
424       (Scope, Name, LinkageName, File, Line, Type, IsLocalToUnit, IsDefinition,
425        ScopeLine, ContainingType, Virtuality, VirtualIndex, ThisAdjustment,
426        Flags, IsOptimized, Unit, TemplateParams, Declaration, Variables));
427   Metadata *Ops[] = {File,           Scope,       Name,           Name,
428                      LinkageName,    Type,        ContainingType, Unit,
429                      TemplateParams, Declaration, Variables};
430   DEFINE_GETIMPL_STORE(DISubprogram, (Line, ScopeLine, Virtuality, VirtualIndex,
431                                       ThisAdjustment, Flags, IsLocalToUnit,
432                                       IsDefinition, IsOptimized),
433                        Ops);
434 }
435 
436 bool DISubprogram::describes(const Function *F) const {
437   assert(F && "Invalid function");
438   if (F->getSubprogram() == this)
439     return true;
440   StringRef Name = getLinkageName();
441   if (Name.empty())
442     Name = getName();
443   return F->getName() == Name;
444 }
445 
446 DILexicalBlock *DILexicalBlock::getImpl(LLVMContext &Context, Metadata *Scope,
447                                         Metadata *File, unsigned Line,
448                                         unsigned Column, StorageType Storage,
449                                         bool ShouldCreate) {
450   // Fixup column.
451   adjustColumn(Column);
452 
453   assert(Scope && "Expected scope");
454   DEFINE_GETIMPL_LOOKUP(DILexicalBlock, (Scope, File, Line, Column));
455   Metadata *Ops[] = {File, Scope};
456   DEFINE_GETIMPL_STORE(DILexicalBlock, (Line, Column), Ops);
457 }
458 
459 DILexicalBlockFile *DILexicalBlockFile::getImpl(LLVMContext &Context,
460                                                 Metadata *Scope, Metadata *File,
461                                                 unsigned Discriminator,
462                                                 StorageType Storage,
463                                                 bool ShouldCreate) {
464   assert(Scope && "Expected scope");
465   DEFINE_GETIMPL_LOOKUP(DILexicalBlockFile, (Scope, File, Discriminator));
466   Metadata *Ops[] = {File, Scope};
467   DEFINE_GETIMPL_STORE(DILexicalBlockFile, (Discriminator), Ops);
468 }
469 
470 DINamespace *DINamespace::getImpl(LLVMContext &Context, Metadata *Scope,
471                                   Metadata *File, MDString *Name, unsigned Line,
472                                   StorageType Storage, bool ShouldCreate) {
473   assert(isCanonical(Name) && "Expected canonical MDString");
474   DEFINE_GETIMPL_LOOKUP(DINamespace, (Scope, File, Name, Line));
475   Metadata *Ops[] = {File, Scope, Name};
476   DEFINE_GETIMPL_STORE(DINamespace, (Line), Ops);
477 }
478 
479 DIModule *DIModule::getImpl(LLVMContext &Context, Metadata *Scope,
480                             MDString *Name, MDString *ConfigurationMacros,
481                             MDString *IncludePath, MDString *ISysRoot,
482                             StorageType Storage, bool ShouldCreate) {
483   assert(isCanonical(Name) && "Expected canonical MDString");
484   DEFINE_GETIMPL_LOOKUP(
485       DIModule, (Scope, Name, ConfigurationMacros, IncludePath, ISysRoot));
486   Metadata *Ops[] = {Scope, Name, ConfigurationMacros, IncludePath, ISysRoot};
487   DEFINE_GETIMPL_STORE_NO_CONSTRUCTOR_ARGS(DIModule, Ops);
488 }
489 
490 DITemplateTypeParameter *DITemplateTypeParameter::getImpl(LLVMContext &Context,
491                                                           MDString *Name,
492                                                           Metadata *Type,
493                                                           StorageType Storage,
494                                                           bool ShouldCreate) {
495   assert(isCanonical(Name) && "Expected canonical MDString");
496   DEFINE_GETIMPL_LOOKUP(DITemplateTypeParameter, (Name, Type));
497   Metadata *Ops[] = {Name, Type};
498   DEFINE_GETIMPL_STORE_NO_CONSTRUCTOR_ARGS(DITemplateTypeParameter, Ops);
499 }
500 
501 DITemplateValueParameter *DITemplateValueParameter::getImpl(
502     LLVMContext &Context, unsigned Tag, MDString *Name, Metadata *Type,
503     Metadata *Value, StorageType Storage, bool ShouldCreate) {
504   assert(isCanonical(Name) && "Expected canonical MDString");
505   DEFINE_GETIMPL_LOOKUP(DITemplateValueParameter, (Tag, Name, Type, Value));
506   Metadata *Ops[] = {Name, Type, Value};
507   DEFINE_GETIMPL_STORE(DITemplateValueParameter, (Tag), Ops);
508 }
509 
510 DIGlobalVariable *
511 DIGlobalVariable::getImpl(LLVMContext &Context, Metadata *Scope, MDString *Name,
512                           MDString *LinkageName, Metadata *File, unsigned Line,
513                           Metadata *Type, bool IsLocalToUnit, bool IsDefinition,
514                           Metadata *Variable,
515                           Metadata *StaticDataMemberDeclaration,
516                           StorageType Storage, bool ShouldCreate) {
517   assert(isCanonical(Name) && "Expected canonical MDString");
518   assert(isCanonical(LinkageName) && "Expected canonical MDString");
519   DEFINE_GETIMPL_LOOKUP(DIGlobalVariable,
520                         (Scope, Name, LinkageName, File, Line, Type,
521                          IsLocalToUnit, IsDefinition, Variable,
522                          StaticDataMemberDeclaration));
523   Metadata *Ops[] = {Scope, Name,        File,     Type,
524                      Name,  LinkageName, Variable, StaticDataMemberDeclaration};
525   DEFINE_GETIMPL_STORE(DIGlobalVariable, (Line, IsLocalToUnit, IsDefinition),
526                        Ops);
527 }
528 
529 DILocalVariable *DILocalVariable::getImpl(LLVMContext &Context, Metadata *Scope,
530                                           MDString *Name, Metadata *File,
531                                           unsigned Line, Metadata *Type,
532                                           unsigned Arg, unsigned Flags,
533                                           StorageType Storage,
534                                           bool ShouldCreate) {
535   // 64K ought to be enough for any frontend.
536   assert(Arg <= UINT16_MAX && "Expected argument number to fit in 16-bits");
537 
538   assert(Scope && "Expected scope");
539   assert(isCanonical(Name) && "Expected canonical MDString");
540   DEFINE_GETIMPL_LOOKUP(DILocalVariable,
541                         (Scope, Name, File, Line, Type, Arg, Flags));
542   Metadata *Ops[] = {Scope, Name, File, Type};
543   DEFINE_GETIMPL_STORE(DILocalVariable, (Line, Arg, Flags), Ops);
544 }
545 
546 DIExpression *DIExpression::getImpl(LLVMContext &Context,
547                                     ArrayRef<uint64_t> Elements,
548                                     StorageType Storage, bool ShouldCreate) {
549   DEFINE_GETIMPL_LOOKUP(DIExpression, (Elements));
550   DEFINE_GETIMPL_STORE_NO_OPS(DIExpression, (Elements));
551 }
552 
553 unsigned DIExpression::ExprOperand::getSize() const {
554   switch (getOp()) {
555   case dwarf::DW_OP_bit_piece:
556     return 3;
557   case dwarf::DW_OP_plus:
558   case dwarf::DW_OP_minus:
559     return 2;
560   default:
561     return 1;
562   }
563 }
564 
565 bool DIExpression::isValid() const {
566   for (auto I = expr_op_begin(), E = expr_op_end(); I != E; ++I) {
567     // Check that there's space for the operand.
568     if (I->get() + I->getSize() > E->get())
569       return false;
570 
571     // Check that the operand is valid.
572     switch (I->getOp()) {
573     default:
574       return false;
575     case dwarf::DW_OP_bit_piece:
576       // Piece expressions must be at the end.
577       return I->get() + I->getSize() == E->get();
578     case dwarf::DW_OP_plus:
579     case dwarf::DW_OP_minus:
580     case dwarf::DW_OP_deref:
581       break;
582     }
583   }
584   return true;
585 }
586 
587 bool DIExpression::isBitPiece() const {
588   assert(isValid() && "Expected valid expression");
589   if (unsigned N = getNumElements())
590     if (N >= 3)
591       return getElement(N - 3) == dwarf::DW_OP_bit_piece;
592   return false;
593 }
594 
595 uint64_t DIExpression::getBitPieceOffset() const {
596   assert(isBitPiece() && "Expected bit piece");
597   return getElement(getNumElements() - 2);
598 }
599 
600 uint64_t DIExpression::getBitPieceSize() const {
601   assert(isBitPiece() && "Expected bit piece");
602   return getElement(getNumElements() - 1);
603 }
604 
605 DIObjCProperty *DIObjCProperty::getImpl(
606     LLVMContext &Context, MDString *Name, Metadata *File, unsigned Line,
607     MDString *GetterName, MDString *SetterName, unsigned Attributes,
608     Metadata *Type, StorageType Storage, bool ShouldCreate) {
609   assert(isCanonical(Name) && "Expected canonical MDString");
610   assert(isCanonical(GetterName) && "Expected canonical MDString");
611   assert(isCanonical(SetterName) && "Expected canonical MDString");
612   DEFINE_GETIMPL_LOOKUP(DIObjCProperty, (Name, File, Line, GetterName,
613                                          SetterName, Attributes, Type));
614   Metadata *Ops[] = {Name, File, GetterName, SetterName, Type};
615   DEFINE_GETIMPL_STORE(DIObjCProperty, (Line, Attributes), Ops);
616 }
617 
618 DIImportedEntity *DIImportedEntity::getImpl(LLVMContext &Context, unsigned Tag,
619                                             Metadata *Scope, Metadata *Entity,
620                                             unsigned Line, MDString *Name,
621                                             StorageType Storage,
622                                             bool ShouldCreate) {
623   assert(isCanonical(Name) && "Expected canonical MDString");
624   DEFINE_GETIMPL_LOOKUP(DIImportedEntity, (Tag, Scope, Entity, Line, Name));
625   Metadata *Ops[] = {Scope, Entity, Name};
626   DEFINE_GETIMPL_STORE(DIImportedEntity, (Tag, Line), Ops);
627 }
628 
629 DIMacro *DIMacro::getImpl(LLVMContext &Context, unsigned MIType,
630                           unsigned Line, MDString *Name, MDString *Value,
631                           StorageType Storage, bool ShouldCreate) {
632   assert(isCanonical(Name) && "Expected canonical MDString");
633   DEFINE_GETIMPL_LOOKUP(DIMacro, (MIType, Line, Name, Value));
634   Metadata *Ops[] = { Name, Value };
635   DEFINE_GETIMPL_STORE(DIMacro, (MIType, Line), Ops);
636 }
637 
638 DIMacroFile *DIMacroFile::getImpl(LLVMContext &Context, unsigned MIType,
639                                   unsigned Line, Metadata *File,
640                                   Metadata *Elements, StorageType Storage,
641                                   bool ShouldCreate) {
642   DEFINE_GETIMPL_LOOKUP(DIMacroFile,
643                         (MIType, Line, File, Elements));
644   Metadata *Ops[] = { File, Elements };
645   DEFINE_GETIMPL_STORE(DIMacroFile, (MIType, Line), Ops);
646 }
647 
648